Door spring

ABSTRACT

A device adapted to return a door to its closing position after it has been opened. The device comprises a cam adapted to be fixed on the door and a casing adapted to be fixed on the frame of the door, the casing comprises a spring exerting a force on a roller which is held in contact with the curve of the cam and means adapted to control the force of the roller on the cam, the cam and the casing being provided with means to adjustably mount them on the door and the frame.

I United States Patent 11 1 1111 3,763,519 Favre Get. 9, 1973 [54] DOORSPRING 2,694,389 11/1954 Turkish 74/569 O 1 Invent Lucien Gland,Swnzehand 531;??? 311320 52121 .Iffik [22] Filed: May 1971 FOREIGNPATENTS OR APPLICATIONS [21] App]. N0; 144,842 777,449 2/1968 Canada16/190 1,263,866 4/1902 France 74/569 [30] Foreign Apphc atlou PnontyData Primary ExaminerBernard A. Gelak Jan. 8, 1971 Switzerland 299/71Assistant Examiner peter A Aschenbrenner Att -R d A. R b [52] us. c116/72, 16/190, 16/145, 9

16/129 51 1111.0 E051 H08 [57] ABSTRACT [58] Field of Search 16/72, 80,145, 85, A device adapted to return a door to its closing posi- 16/129,180, 190, 181, 182, 86 A; 74/569 .tion after it has been opened.

The device comprises a cam adapted to be fixed on [56] References C'tedthe door and a casing adapted to be fixed on the frame UNITED STATESPATENTS of the door, the casing comprises a spring exerting 21 1,645,97710/1927 Titus 16/80 x force on a roller which is held in Contact withthe 753,998 3/1904 Moore 16/72 curve of the cam and means adapted tocontrol the 328,192 10/1885 Coultaus 16/71 force of the roller on thecam, the cam and the casing 2,219,820 l0/ 9 SChOniIZerm 16/35 X beingprovided with means to adjustably mount them 967,289 8/1910 Adam 16/72on the door d the f 1,987,512 l/l935 Leonard 16/180X 2,580,152 12/1951Bergstrom et a1. 74/569 3 Claims, 2 Drawing Figures noon SPRING FIELD OFTHE INVENTION The present invention relates to a door closure.

DESCRIPTION OF THE PRIOR ART Devices are known that bring a door back toits closed position after the latter having been opened. These devicesare spring actuated and are provided with a brake system to prevent asudden release of the spring. Such a brake system which usually uses thecompression of a liquid or air requires a very precise setting. In orderto obtain such a setting, complicated means must be foreseen. For thisreason, the cost of these devices is rather high. Furthermore, theoperation of these devices may sometimes fail when the temperatures varyconsiderably and in particular when these temperatures are very low.Another disadvantage of these devices consists in the fact that a lightpressure on the door may cause it to open.

SUMMARY OF THE INVENTION An object of the present invention istoovercome the above-mentioned disadvantages. I

More specifically, the invention is a door closure for closing anopening formed by a frame part and a door part swingingly connected tothe frame part, this closure comprising: a cam fixed to one of the partsand having a camming edge; a follower fixed to the other part andincluding a follower roller and resilient means biasing the rolleragainst the camming edge for constant application thereagainst. Theaforementioned camming edge is' formed, in succession, of a straightportion that extends at right angle to the said one part, a curvedportion that extends in a direction away from the follower and a stopnotch adapted-to receive the follower roller to hold the door part inopen position.

BRIEF DESCRIPTION OF THE DRAWING A drawing is annexed to illustrate anembodiment of the invention, wherein FIG. 1 is a top plan view of thedoor closure when the door is slightly open;

FIG. 2 is a front view of the door spring mounted at the top of thedoor.

DESCRIPTION OF THE PREFERRED EMBODIMENT The door closure shown in-thedrawing comprises a cam provided with a curved surface 11. The cam 10 isfixed by means of a metallic strip 12 in a corner located at the top ofthe frame 13 of the door. This strip 12 is provided with elongated slot'14 through which screws are inserted to fasten the strip to the frame13 of the door. On account ,of the'elong ated slot 14 provided in themetallic strip 12, the cam 10 may take a desired orientation relative tothe frame 13 of the door and then rigidly fixed by means of the screws15 on the said frame. The leaf 16 which is swingingly mounted in theframe of the door by some known means, is provided with a strip 17 inwhich is fixed a support 18 provided with means which cooperate with thecam 10. The support 18 is provided with slots 19 through which thescrews 20 pass to rigidly secure the strip 17. The elongation of theslots 19 enables the support 18 to take a variety of orientations overthe strips 17 carried by the leaf l6.

The support 18 carries follower assembly formed of a casing 21 in whichis located a roller holder 22 and a roller 23 extending outside thecasing 21. The roller holder 22 is under the action of a force exertedby a spring 24 located inside the casing 21. The end of the casing 21opposite the roller 23 is provided with a threaded hole through which ismounted a setting screw 25. The screw 25 is adapted to exert a pressureon a small plate 26 which is in contact with the spring 24. When thesetting screw 25 is rotated, the force exerted by the spring may becontrolled.

The roller 23 is located in such a way as to come in contact with thecurved surface 11 of the cam 10. The pressure at which the roller 23 isapplied against the curved surface 11 of the cam 10 may be varied andadjusted by means of the setting screw 25.

The curved surface 11 is provided at the end of the path of the roller23, with a notch 27 in which the roller 23 can be lodged. In thisposition, the leaf remains open and the door does not close by itself bymeans of the door closure.

The operation of the door closure, as described above, is as follows:

When the leaf 16 is open, the roller 23 moves from a straight surface aof the camming surface 11 to a surface b curving in the direction ofopening of the door. The roller is pushed inwardly of the housing 21 bythe cam 10 and against the pressure exerted by the spring 24. As soon asthe pressure exerted on the leaf stops, the latter is brought back toits closing position by means of the door spring. For this purpose, thespring applies a pressure against the roller holder 22 and this pressureis transmitted by means of the roller 23 on the camming surface 11 ofthe cam 10. The closing of the leaf 16 takes place in such a way that aslong as the roller 23 rides on the curved surface b, the door closesrelatively slowly. But as soon as it comes in contact with the straightsurface a, extending substantially at right angle to the door frame 13,the door closes rather abruptly ensuring complete closure thereof. Oncethe door is closed, it will not open by itself.

The pressure which is necessary to open the door may be controlled bymeans of the setting screw 25. The position of the cam 10 which is alsoadjustable, also influences the pressure with which the leaf 16 isapplied against the frame 13. As stated above, the various parts of thedoor closure may be fixed to the frame 13 of the door and to the leaf 16in such a way that they may be moved and adjusted as well as solidlyfixed in a desired position.

Every part of the door closure which constitute the above-describedembodiment are simple to manufacture. This lowers its cost as comparedto the known devices.

An alternative embodiment of the above-described invention would consistin that the cam with its camming surface 11 be fixed to the leaf 16. Thesupport 18 as well as the parts cooperating with the cam 10 would thenbe fixed to the frame 13 of the door.

I claim:

1. A door closure for closing an opening formed by a frame part and adoor part swingingly connected to said frame part, said closurecomprising:

a. a cam fixed to one of said parts and having a camming edge;

b. a follower fixed to the other part and including a follower rollerand resilient means biassing said roller against said camming edge forconstant application thereagainst, and

c. wherein said camming edge is formed, in succession, of a straightportion extending at right angle to said one of such part, a curvedportion extending in a direction away from said follower and a stopnotch adapted to receive said follower roller to hold said door part inopen position,

whereby, when said door part moves from open to closed position, saidbiassed roller first rides on said curved portion to force said door toclose relatively slowly and then rides on said straight portion to allowsaid door part to move abruptly towards said frame part to ensurecomplete closure.

2. A door closure as claimed in claim 1 wherein said cam is fixed tosaid frame part and means so fixing it as to allow displacement of saidcamming surface with respect to said follower roller.

3. A door closure as claimed in claim 2 wherein said follower is fixedto said door part and comprises a casing, a roller holder rod slidablyreceived in said casing to which said follower roller is mounted and aspring in said casing biassing said rod and roller outwardly againstsaid camming edge, and means fixing said casing to said door partadjustably in longitudinal direction whereby said casing may bedisplaced longitudinally to vary the biassing pressure acting on saidroller.

1. A door closure for closing an opening formed by a frame part and adoor part swingingly connected to said frame part, said closurecomprising: a. a cam fixed to one of said parts and having a cammingedge; b. a follower fixed to the other part and including a followerroller and resilient means biassing said roller against said cammingedge for constant application thereagainst, and c. wherein said cammingedge is formed, in succession, of a straight portion extending at rightangle to said one of such part, a curved portion extending in adirection away from said follower and a stop notch adapted to receivesaid follower roller to hold said door part in opEn position, whereby,when said door part moves from open to closed position, said biassedroller first rides on said curved portion to force said door to closerelatively slowly and then rides on said straight portion to allow saiddoor part to move abruptly towards said frame part to ensure completeclosure.
 2. A door closure as claimed in claim 1 wherein said cam isfixed to said frame part and means so fixing it as to allow displacementof said camming surface with respect to said follower roller.
 3. A doorclosure as claimed in claim 2 wherein said follower is fixed to saiddoor part and comprises a casing, a roller holder rod slidably receivedin said casing to which said follower roller is mounted and a spring insaid casing biassing said rod and roller outwardly against said cammingedge, and means fixing said casing to said door part adjustably inlongitudinal direction whereby said casing may be displacedlongitudinally to vary the biassing pressure acting on said roller.